A small party, not quite full scale. Generally a shindig consists of 5-20 people hanging out at the host's house, but they may be held at other locations such as a beach. Shindigs almost always involve alcoholic beverages, usually beer. Often, marijuana is smoked as well.

A shindig usually does not escalate into a large full scale party because it is meant to be a low key night, avoiding any complications such as cleaning up vomit, unwanted guests, picking up trash the rude guests leave lying wherever they drop it, putting everything back in its proper place, eliciting attention fom neighbors and local law enforcement, etc.

My mom was out for the day, so I called some of my friends and we had a little shindig.

shin dig is a set of words that can be used in a similar fashion as "thing." Shin dig can refer to any place or thing, however it is often used when speaking of an event such as a party or happening of some kind.

We went to the shin dig at my friends house and met a lot of people there. There was a live band and party games.

A small gathering where alcohol is involved... something you wouldn't quite call a "party" but something a little bit more than hangin out with your sister and your dog and a bottle of rum. Maximum number of people for a shindig: no more than 12, otherwise it's a small party.

"I'm havin a shindig tonight"

or

"Dave's having a few people in Friday night... sortof a shindig - not really a big party or anything"

A small gathering where alcohol is involved... something you wouldn't quite call a "party" but something a little bit more than hangin out with your sister and your dog and a bottle of rum. Maximum number of people for a shindig: no more than 12, otherwise it's a small party.

"I'm havin a shindig tonight"

or

"Dave's having a few people in Friday night... sortof a shindig - not really a big party or anything"